Frisii

The Frisii were a Germanic tribe that inhabited the present-day Netherlands at the time of the Roman Empire. The Frisii gave their name to the Frisia region, and they are ancestors of the modern Frisians.

History
The Frisii were centered around Flevium in Magna Germania (present-day Nehterlands), and they agreed to a trade agreement with Octavian's Rome in 41 BC. However, the Frisii later became enemies of the Roman Republic's Belgae allies, so the Romans conquered Flevium.